1. Field of the Invention
This invention relates to devices and methods for the phototherapeutic treatment of illness and diseases.
2. General Background
Phototherapy is a promising clinical tool for the treatment for many conditions, including seasonal affective disorder, bulimia nervosa, herpes, psoriasis, sleep disorders, acne, and skin cancer.
Phototherapy is especially promising as a treatment for hyperbilirubinemia, a common condition affecting 60-70% of all full-term infants. Hyperbilirubinemia is caused by the accumulation of excess bilirubin in the blood and skin of the infant. This excess bilirubin turns the skin and sclera a characteristic yellow color. If left untreated, extreme cases of hyperbilirubinemia can result in neurological insult (kernicterus) or even death. A common treatment for hyperbilirubinemia is phototherapy, in which the infant is exposed to light in a range corresponding to the peak absorption spectra for bilirubin (blue-green, 400-520 nm). This light changes the form of the bilirubin to a different isomer that is more readily eliminated by the body.
A number of different light sources can be used for phototherapy. Traditionally, broadband sources have been used, such as fluorescent, halogen, or incandescent light. However, it has been recently suggested that light emitting diodes (LEDs) can be an effective phototherapeutic light source.
Blue LEDs have been effectively used to treat hyperbilirubinemia, but some individuals report a feeling of nausea or discomfort from prolonged exposure to blue light. Thus, there is a need for a method of relieving the discomfort these individuals feel, without compromising the effectiveness of the phototherapy.